Dust collector systems for filtering and collecting dust, dirt, and other fine particulate from a particulate-laden air stream commonly include air filters, such as air filter cartridges, for filtering the dust from the clean air. The cartridges are mounted in a plate, commonly referred to as a tube sheet or a cell plate, that separates the dust collector into a lower, dirty air chamber and an upper, clean air chamber. The air filter cartridges include filter media that tend to accumulate at least a portion of the separated dust. To maintain an efficient filtering system, the dust accumulated on the filter media must be at least partially removed, especially if the dust collects in a relatively thick layer.
To dislodge the collected dust from the filter media and otherwise refresh the media, dust collector systems commonly direct pressurized air against and through the air filter cartridges in pulses, i.e., intermittently. To direct the pressurized air against and through the filter cartridges, a pipe, commonly referred to as a purge pipe, is positioned approximately 2-10 inches above the air filter cartridge. The pipe includes small openings through a bottom of the pipe facing the air filter cartridge. The pipe is fluidly connected to a pulse valve that controls pressurized air passing through the pipe, the openings in the pipe, and the air filter cartridge. The pressurized air assists in dislodging collected dust from the filter media.
Although pressurized pulse cleaning of the air filter cartridge increases the wear life of the cartridge, over time the filter media will become so particulate laden that the cartridge will need to be replaced. To replace the air filter cartridge, the purge pipe positioned over each cartridge must be removed to gain access to the cartridge. In larger size cartridge style dust collector systems, there may be dozens of purge pipes that must be removed to service the system. After removal, these pipes must be laid aside to access the cartridges.
Each purge pipe is also typically connected to the pulse valve in an air tight connection with either a compression coupling, a threaded union, a flexible hose and clamps, or other securement mechanism requiring tools to install or remove. Additionally, not only must the purge pipe be connected to the pulse valve in an air tight communication, it should be securely positioned within the system and not susceptible to any movement during operation. Otherwise, there may be a misalignment of the holes in the purge pipe and over the air filter cartridges, which results in less than optimal cleaning of the filter media.
Because dust collector system are often mounted several feet to tens of feet off the ground and with little excess room for an operator to move during service of the system, loose parts, such as removed purge pipes and their securement mechanisms, become a safety hazard. For example, the minimal amount of work space to service the system can result in the operator accidentally tripping on a purge pipe or having a pipe fall from the dust collector. There is also a danger of dropping loose parts, such as a coupling, a hose clamp, or other securement mechanism, or the tools used during servicing of the system, such as a wrench. Additionally, loose pipes and other parts can be dropped through the openings in the tube sheet once the cartridges are removed. If these pipes, tools, or other parts are dropped through the tube sheet and not recovered, they could be transferred into other downstream processing equipment, which could cause severe damage to that equipment.
Notwithstanding the possibility of dropping or misplacing parts as described above, it is also time consuming for the operator to remove and then reinstall the purge pipes, especially if there are multiple purge pipes for large systems.
Accordingly, there is a need for a dust collector system and, in particular, a pulsed air system, that reduces installation and maintenance costs and time required for removing or installing the filter cartridges. Moreover, there is a need for a pulsed air system and, in particular, an air distribution assembly comprising a plurality of purge pipes that can be readily removed without use of tools and without dismantling or otherwise removing the purge pipes from the dust collector system.